Electric switch.



No. 876,910. PATENTED JAN. 14, 1908. G. G. PERKINS.

ELECTRIC SWITCH.

APPLICATION FILED FEB. 19, 1906.

UNITED STATES PATENT OFFICE.

CHARLES G. PERKINS, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE PERKINS COR- PORATION, OF HARTFORD, CONNECTICUT, A CORPORATION OF CONNECTICUT.

ELECTRIC SWITCH.

Specification of Letters Patent.

Patented Jan. 14, 1908.

Application filed February 19i1906. Serial No. 301.794.

Hartford, in the county of Hartford and State of Connecticut, have invented a new and useful Electric Switch, of which the following is a specification.

This invention'relates to a fusible knife switch.

The object of the invention is to provide a simple and cheap switch of this character which is so constructed'that the fuse or fuses can be easily and quickly applied or re moved, and which has its terminals and contacts so arranged that there is no liability of short-circuiting the switch or shocking the electrician when the circuit wires are being connected or disconnected or the fuse or fuses being applied or removed or by any tool or other means when the switch is in service. In this knife switch the oscillating contacts join the stationary contacts that are connected with the line terminals and the stationary contacts that are connected with the fuse terminals so that closing the switch completes the circuit through the fuse or fuses and'opening the switch interrupts the circuit through the fuse or fuses. When the switch is open the fuse terminals'are dead.

Figure 1 of the accom anying drawings shows a plan of a two-wire 'fe-sw'itch, with the cover omitted, that embodies theinvention. 2 shows a side elevation of the same with the cover cut in section. Fi 3 is a transverse section on larger scale, ta en on the plane indicated by the line 33 on Fig. 1. Fig. 4 shows a plan of a single wire switch that embodies the invention. Fig. 5 shows one form of stationary and oscillating contacts which may be used. Fig. 6 is a plan of the stationary contacts shown in ig. 5. Fig. 7 shows another form of contacts which may be used. And Fig. 8 shows still another arrangement of contacts.

The base 1 which is preferably rectangular in outline may be formed of porcelain, slate or any other suitable insulating material.

In the two-wire switch first. shown there are four plates 2 fastened to the up or surface of the base and each is provided with a binding screw 3 for fastening. the ends ,of the line wires. Extending upwardly from each of these plates may be a single contact 4.

mon inclosed safety fuses. stead of having these terminals formed in Adjacent to but not in contact with each of these plates isra plate 5 which may be provided with a single upwardly extendingcontact 6. Secured to each of these latter plates may be a pair of spring fingers 7 that will receive the cap terminal 8 of an inclosed safety fuse 9. I

Fastened to the upper surface of the base near one end are ears 10 and hingedto these are bars 11 of insulatin materiaL. These bars are connected by a ar 12, which has a handle 13.

Fastened to'the hinged bars so as to engage the line wire contacts and the fuse terminal contacts that extend upwardly from the base may be the double oscillatory contacts 14. When the switch is closed these oscillating contacts form a connection between the stationary contacts on the-base in such manner that the circuit is completed through the fuses, that is, the movable contacts connect the line wire contacts with the adjacent fuse terminal contacts. When the switch is open there is no connection between the line wire contacts and the fuse terminal contacts, that is, when the switch is open the fuse terminals are not alive so that a fuse can be inserted or removed without danger of short-circuiting the switch or receiving a shock by accidental contact.

Instead of having each line wire and fuse terminal contact that extends upwardly from' the base formed of a single piece as above described, and as shown in Fig. 5, each contact may be formed of two pieces 15, as shown in Fig. 7, in which case, of course, the contacts 16 that are fastened to the swinging part of the switch will be formed of one piece instead of two, or each line contact may be formed of a single piece 17, and each fuse terminal contact may be formed of a single piece 18, and the swinging contact may be a and 19 on the bar, as shown in Fig. 8.

In the form first shown and described the fuse terminals are spring fingers arranged to receive and grasp caps on the ends of com- If desired, in-

this manner, posts 20 having binding screws 21 may be used for fastening the ends of the fuses, as shown in Figs. 4 and 7 of the drawings, or walls 22 may be arranged for'receiving the ends of the fuses, as shown in Fig. 8.

These switches may be constructed for a single wire, as shown in Fi 4, or for two wires, as shown in Fig. 1. f it is desired to arrange them for three or more wires the parts are merely duplicated.

In order to isolate the parts it is desirable to have a longitudinally etxending wall 23 of insulating material between the fuses and also a transversely-extending wall 24. It is also desirable to secure a cover 25 of insulating material to the swinging portion of the switch in such manner that when the circuits are closed the cover closes in and entirely conceals the contacts and the fuses, but which when the switch is opened moves away so that the fuses are accessible.

In ordinary use the switch is opened and closed by swinging the handle. If it is desired to open the switch and have the handle down and the cover closed one or both fuses may be removed. This construction provides a fusible switch in which the fuses form a part of the circuit between the terminals and yet are stationary and are so connected that they may be freely removed and replaced without danger of causing any short-.

circuit, that is, the fuse terminals are. dead whenever the switch is open.

The invention claimed is An electric switch havin a base, an insulated bar hinged to the ase, a line terminal fastened to the base near the hinged end of the bar, a fuse terminal fastened to the base near the hinged end of the bar, a line terminal fastened to the base near the free end of the bar, a fuse terminal fastened to the base near the free end of the bar, said fuse terminals being adapted to be connected by a fuse that extends parallel with the bar, an electrical contact carried by the bar and adapted to be engaged with and disengaged from the line and fuse terminals near the hinged end of the bar and an electrical contact insulated from the former contact and adapted to connect the line and fuse terminals near the free end ,of the bar, substantially as specified.

CHARLES G. PERKINS.

Witnesses:

HARRY R. WILLIAMS, BENJ. C. PERKINS. 

